clk: at91: pmc: add helpers for clock drivers

Add helper for clock drivers. These will be used by following
commits in the process of switching AT91 clock drivers to CCF.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 517ba1d..b1ab0a9 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -8,6 +8,12 @@
 #define __AT91_PMC_H__
 
 #include <regmap.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+
+/* Keep a range of 256 available clocks for every clock type. */
+#define AT91_TO_CLK_ID(_t, _i)		(((_t) << 8) | ((_i) & 0xff))
+#define AT91_CLK_ID_TO_DID(_i)		((_i) & 0xff)
 
 struct pmc_platdata {
 	struct at91_pmc *reg_base;
@@ -20,4 +26,11 @@
 int at91_clk_of_xlate(struct clk *clk, struct ofnode_phandle_args *args);
 int at91_clk_probe(struct udevice *dev);
 
+int at91_clk_mux_val_to_index(const u32 *table, u32 num_parents, u32 val);
+int at91_clk_mux_index_to_val(const u32 *table, u32 num_parents, u32 index);
+
+void pmc_read(void __iomem *base, unsigned int off, unsigned int *val);
+void pmc_write(void __iomem *base, unsigned int off, unsigned int val);
+void pmc_update_bits(void __iomem *base, unsigned int off, unsigned int mask,
+			unsigned int bits);
 #endif